The proposed project seeks to provide conceptual and normative analyses of three ideas that are often invoked in debates over the prospects of human genetic engineering. These concepts are: 1) "Homo sapiens" (a biological species concept); 2) "person" (an ethical and a legal concept); and 3) "human being" (a cultural and aesthetic concept). The Investigators believe that philosophical clarification of these concepts as they arise in debates over the possibility of technological interventions into the human genome can strengthen contemporary discussion of ethical, legal, and social implications of the Human Genome Project. The project would review and assess the growing literature on germ-line intervention and human nature in relation to the differences among these three concepts. The project would produce philosophical analyses that will explicate possible limits on germ-line engineering that may be justified in terms of maintaining the character or status of individuals as members of a historical species, as possessing free will or moral responsibility, and -- most importantly -- as sharing a cultural identity as human beings. The project aims specifically 1) To analyze the properties associated with human nature - or the aspects of our shared humanity -- that restrictions on germ-line engineering may seek to protect or preserve; 2) To show how assumptions about human nature can be analyzed and clarified in terms of logical relationships among three different concepts: Homo sapiens, human being, and person; and 3) To produce a series of essays to be collected into a book, along with other articles, conference presentations, and policy-related papers, which will analyze and evaluate proposals that appeal to any of these three concepts as normative principles or reasons to ban or regulate applications of genetic technologies to the human genome.